Field of the invention
The present invention relates to a method for dredging an underwater bottom in an area using a dredging device. The invention likewise relates to a computer program comprising program instructions for performing of the method by a computer. The invention also relates to a computer configured to run such a computer program.
Description of Related Art
In the dredging of an underwater bottom a cutting member of a dredging device, such as for instance the suction head of a trailing suction hopper dredger or the cutter head of a cutter suction dredger in stationary position, is advanced over the underwater bottom. Dislodged soil particles are suctioned up here via a suction pipe connected to the dredging device.
In the dredging of an area it is of great importance to take into account unforeseen events which may cause damage to the area. It is thus possible for instance for the water temperature to rise too high, which results in death of flora and fauna. The water temperature could for instance rise when a power plant discharges its water in or close to the area for dredging or raising, whereby the local hydrodynamics are disrupted or break down. Another example relates to the dredging of a freshwater area adjoining a saltwater area, wherein the salt content (or salinity) could suddenly increase.
A particularly important example concerns an increased turbidity of the water as a result of entry into the water of fine sediment particles which are not suctioned away by the suction pipe, or insufficiently so. This source of contamination, generated by the dredging itself, can cause damage to for instance coral reefs. In the case of a trailing suction hopper dredger the fine particles can for instance enter the water via the overflow of the bin of the trailing suction hopper dredger and form a plume which spreads over the area for dredging behind the trailing suction hopper dredger.
The present invention has for an object to provide a method for dredging an underwater bottom, wherein on the one hand the production is maximized and on the other the consequences for the natural environment are minimized in accordance with requirements laid down therefor.